MADRAS AGRICULTURAL JOURNAL

Apoplast associated microbes Influences Antioxidant System of Rice under Drought Stress

Abstract

                                Rice is the staple food crop for more than 60 per cent of the world population. In order to feed the growing population, rice productivity need to be increased using sustainable technologies under changing climatic condition, especially prolonged moisture stress. Water stress is a limiting factor in agriculture production by preventing a crop from reaching the genetically determined theoretical maximum yield. To overcome this issues, environmental friendly mitigation technologies such as the use of beneficial microbes to alleviate drought stress are warranted. With this aim, a pot culture experiment was conducted with rice variety CO51. Rice seeds were biotized with apoplastic bacterial strain Bacillus methylotrophicus RABA6 and yeast strain Candida tropicalis RAYN2. Among the treatments, B. methylotrophicus RABA6 inoculated plants exhibited highest cell membrane stability, enzymatic antioxidants (Catalase, Peroxidase and Superoxide dismutase) activities, non-enzymatic antioxidant content (ascorbic acid, total phenol, total anthocyanin, carotenoids and total flavonoid) and decreased content of hydrogen peroxide and superoxide radicles under induced moisture stress.. These results suggest that the use of apoplastic microbes are the effective and eco-friendly technologies for drought mitigation, and further studies are required under field condition..

Key words : Rice, drought, apoplast microbes, Bacillus methylotrophicus, Candida tropicalis, antioxidant and Reactive Oxygen Species.